llvm-project

Commit Graph

Author	SHA1	Message	Date
Chris Lattner	08af5a9dad	implement support for sinking a load out the bottom of a block that has no stores between the load and the end of block. This works great and sinks hundreds of stores, but we can't turn it on because machineinstrs don't have volatility information and we don't want to sink volatile stores :( llvm-svn: 45894	2008-01-12 00:17:41 +00:00
Chris Lattner	c8226f32e9	Simplify the side effect stuff a bit more and make licm/sinking both work right according to the new flags. This removes the TII::isReallySideEffectFree predicate, and adds TII::isInvariantLoad. It removes NeverHasSideEffects+MayHaveSideEffects and adds UnmodeledSideEffects as machine instr flags. Now the clients can decide everything they need. I think isRematerializable can be implemented in terms of the flags we have now, though I will let others tackle that. llvm-svn: 45843	2008-01-10 23:08:24 +00:00
Chris Lattner	f3bd2cd37c	Clamp down on sinking of lots of instructions. llvm-svn: 45841	2008-01-10 22:35:15 +00:00
Chris Lattner	ee61d14bf6	The current impl is really trivial, add some comments about how it can be made better. llvm-svn: 45625	2008-01-05 06:47:58 +00:00
Chris Lattner	d11ca169e7	don't sink anything with side effects, this makes lots of stuff work, but sinks almost nothing. llvm-svn: 45617	2008-01-05 02:33:22 +00:00
Chris Lattner	6ec78274df	fix a common crash. llvm-svn: 45614	2008-01-05 01:39:17 +00:00
Chris Lattner	f3edc09f9b	Add a really quick hack at a machine code sinking pass, enabled with --enable-sinking. It is missing validity checks, so it is known broken. However, it is powerful enough to compile this contrived code: void test1(int C, double A, double B, double P) { double Tmp = AA+BB; P = C ? Tmp : A; } into: _test1: movsd 8(%esp), %xmm0 cmpl $0, 4(%esp) je LBB1_2 # entry LBB1_1: # entry movsd 16(%esp), %xmm1 mulsd %xmm1, %xmm1 mulsd %xmm0, %xmm0 addsd %xmm1, %xmm0 LBB1_2: # entry movl 24(%esp), %eax movsd %xmm0, (%eax) ret instead of: _test1: movsd 16(%esp), %xmm0 mulsd %xmm0, %xmm0 movsd 8(%esp), %xmm1 movapd %xmm1, %xmm2 mulsd %xmm2, %xmm2 addsd %xmm0, %xmm2 cmpl $0, 4(%esp) je LBB1_2 # entry LBB1_1: # entry movapd %xmm2, %xmm1 LBB1_2: # entry movl 24(%esp), %eax movsd %xmm1, (%eax) ret woo. llvm-svn: 45570	2008-01-04 07:36:53 +00:00

7 Commits